Anybody know of an information source in respect to RTA’s and those horrid little bell bollards? It appears that they have a nasty habit of flipping vehicles over, anybody had a bad experience with one?
A freedom of information request to Wimbledon council might be a starting point.
from looking at the pictrue in your first link redboxer, how anyone can blame the bollard is beyond me
to hit the bollard, the car must have first mounted the pavement, therefore, being totally the fault of the car driver, not the bollard 
one in morden once ripped the n/s rear wheel of a waltzer truck
it was lucky it was only the single wheel and not the double wheels as the truck would have had to be put on a low loader
and we managed to strap up what was left of the axel and get it to the next place
The ones into my yard goo.gl/maps/UJOFM have only claimed one victim - the Transport Manager 
Caused considerable damage.
I suppose at the end of the day, they are intended to protect any pedestrians waiting to cross. They appear to be quite effective.